Short training field (STF) within wireless communications

ABSTRACT

A wireless communication device (alternatively, device) includes a processor configured to support communications with other wireless communication device(s) and to generate and process signals for such communications. In some examples, the device includes a communication interface and a processor, among other possible circuitries, components, elements, etc. to support communications with other wireless communication device(s) and to generate and process signals for such communications. Short training field (STF) sequences are designed using a base binary sequence. In some examples, the base binary sequence is specified as [−1, −1 −1 +1 +1 +1 −1, +1, +1 +1 −1 +1 +1 −1, +1]. One STF includes the base binary sequence mapped. Another STF includes the base binary sequence followed by 0 followed by a phased rotated version of the base binary sequence. Another STF includes the base binary sequence followed by 0 followed by an inverted version of the base binary sequence.

CROSS REFERENCE TO RELATED PATENTS/PATENT APPLICATIONS ProvisionalPriority Claims

The present U.S. Utility Patent Application claims priority pursuant to35 U.S.C. §119(e) to U.S. Provisional Patent App. Ser. No. 62/128,481,entitled “Short training field (STF) sequences within wirelesscommunications,” filed Mar. 4, 2015; U.S. Provisional Patent App. Ser.No. 62/156,234, entitled “Short training field (STF) sequences withinwireless communications,” filed May 2, 2015; U.S. Provisional PatentApp. Ser. No. 62/216,330, entitled “Short training field (STF) and/orlong training field (LTF) sequences within wireless communications,”filed Sep. 9, 2015; U.S. Provisional Patent App. Ser. No. 62/235,837,entitled “Short training field (STF) and/or long training field (LTF)sequences within wireless communications,” filed Oct. 1, 2015; U.S.Provisional Patent App. Ser. No. 62/240,262, entitled “Short trainingfield (STF) and/or long training field (LTF) sequences within wirelesscommunications,” filed Oct. 12, 2015; U.S. Provisional Patent App. Ser.No. 62/250,207, entitled “Short training field (STF) and/or longtraining field (LTF) sequences within wireless communications,” filedNov. 3, 2015; U.S. Provisional Patent App. Ser. No. 62/256,040, entitled“Short training field (STF) and/or long training field (LTF) sequenceswithin wireless communications,” filed Nov. 16, 2015; U.S. ProvisionalPatent App. Ser. No. 62/258,225, entitled “Short training field (STF)and/or long training field (LTF) sequences within wirelesscommunications,” filed Nov. 20, 2015; U.S. Provisional Patent App. Ser.No. 62/288,544, entitled “Short training field (STF) within wirelesscommunications,” filed Jan. 29, 2016; and U.S. Provisional Patent App.Ser. No. 62/288,583, entitled “Long training field (LTF) within wirelesscommunications,” filed Jan. 29, 2016; all of which are herebyincorporated herein by reference in their entirety and made part of thepresent U.S. Utility Patent Application for all purposes.

Incorporation by Reference

The following U.S. Utility Patent Application is hereby incorporatedherein by reference in its entirety and made part of the present U.S.Utility patent application for all purposes:

1. U.S. Utility Patent Application Ser. No. ______, entitled “Longtraining field (LTF) within wireless communications,” filed concurrentlyon Jan. 30, 2016, pending.

BACKGROUND

1. Technical Field

The present disclosure relates generally to communication systems; and,more particularly, to preamble design for signals within single user,multiple user, multiple access, and/or multiple-input-multiple-output(MIMO) wireless communications.

2. Description of Related Art

Communication systems support wireless and wire lined communicationsbetween wireless and/or wire lined communication devices. The systemscan range from national and/or international cellular telephone systems,to the Internet, to point-to-point in-home wireless networks and canoperate in accordance with one or more communication standards. Forexample, wireless communication systems may operate in accordance withone or more standards including, but not limited to, IEEE 802.11x (wherex may be various extensions such as a, b, n, g, etc.), Bluetooth,advanced mobile phone services (AMPS), digital AMPS, global system formobile communications (GSM), etc., and/or variations thereof.

In some instances, wireless communication is made between a transmitter(TX) and receiver (RX) using single-input-single-output (SISO)communication. Another type of wireless communication issingle-input-multiple-output (SIMO) in which a single TX processes datainto radio frequency (RF) signals that are transmitted to a RX thatincludes two or more antennae and two or more RX paths.

Yet an alternative type of wireless communication ismultiple-input-single-output (MISO) in which a TX includes two or moretransmission paths that each respectively converts a correspondingportion of baseband signals into RF signals, which are transmitted viacorresponding antennae to a RX. Another type of wireless communicationis multiple-input-multiple-output (MIMO) in which a TX and RX eachrespectively includes multiple paths such that a TX parallel processesdata using a spatial and time encoding function to produce two or morestreams of data and a RX receives the multiple RF signals via multipleRX paths that recapture the streams of data utilizing a spatial and timedecoding function.

There continues to be room for improvement of various signal designs foruse in wireless communication systems. There continues to be room forimprovement in the art to design various signals used for variouspurposes including channel estimation, channel characteristic, etc.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a diagram illustrating an embodiment of a wirelesscommunication system.

FIG. 2A is a diagram illustrating an embodiment of dense deployment ofwireless communication devices.

FIG. 2B is a diagram illustrating an example of communication betweenwireless communication devices.

FIG. 2C is a diagram illustrating another example of communicationbetween wireless communication devices.

FIG. 3A is a diagram illustrating an example of orthogonal frequencydivision multiplexing (OFDM) and/or orthogonal frequency divisionmultiple access (OFDMA).

FIG. 3B is a diagram illustrating another example of OFDM and/or OFDMA.

FIG. 3C is a diagram illustrating another example of OFDM and/or OFDMA.

FIG. 3D is a diagram illustrating another example of OFDM and/or OFDMA.

FIG. 3E is a diagram illustrating an example of single-carrier (SC)signaling.

FIG. 4A is a diagram illustrating an example of an OFDM/A packet.

FIG. 4B is a diagram illustrating another example of an OFDM/A packet ofa second type.

FIG. 4C is a diagram illustrating an example of at least one portion ofan OFDM/A packet of another type.

FIG. 4D is a diagram illustrating another example of an OFDM/A packet ofa third type.

FIG. 4E is a diagram illustrating another example of an OFDM/A packet ofa fourth type.

FIG. 4F is a diagram illustrating another example of an OFDM/A packet.

FIG. 5A is a diagram illustrating another example of an OFDM/A packet.

FIG. 5B is a diagram illustrating another example of an OFDM/A packet.

FIG. 5C is a diagram illustrating another example of an OFDM/A packet.

FIG. 5D is a diagram illustrating another example of an OFDM/A packet.

FIG. 5E is a diagram illustrating another example of an OFDM/A packet.

FIG. 6A is a diagram illustrating an example of selection amongdifferent OFDM/A frame structures for use in communications betweenwireless communication devices and specifically showing OFDM/A framestructures corresponding to one or more resource units (RUs).

FIG. 6B is a diagram illustrating an example of various types ofdifferent resource units (RUs).

FIG. 7A is a diagram illustrating another example of various types ofdifferent RUs.

FIG. 7B is a diagram illustrating another example of various types ofdifferent RUs.

FIG. 7C is a diagram illustrating an example of various types ofcommunication protocol specified physical layer (PHY) fast Fouriertransform (FFT) sizes.

FIG. 7D is a diagram illustrating an example of different channelbandwidths and relationship there between.

FIG. 8A is a diagram illustrating an example of a base binary sequencefor use to construct a short training field (STF) for use in wirelesscommunications.

FIG. 8B is a diagram illustrating an example of various STF sequencesfor a first periodicity (e.g., 0.8 μsec).

FIG. 8C is a diagram illustrating another example of a STF sequence fora second periodicity (e.g., 1.6 μsec).

FIG. 9 is a diagram illustrating an embodiment of a method for executionby one or more wireless communication devices.

DETAILED DESCRIPTION

FIG. 1 is a diagram illustrating an embodiment of a wirelesscommunication system 100. The wireless communication system 100 includesbase stations and/or access points 112-116, wireless communicationdevices 118-132 (e.g., wireless stations (STAs)), and a network hardwarecomponent 134. The wireless communication devices 118-132 may be laptopcomputers, or tablets, 118 and 126, personal digital assistants 120 and130, personal computers 124 and 132 and/or cellular telephones 122 and128. Other examples of such wireless communication devices 118-132 couldalso or alternatively include other types of devices that includewireless communication capability. The details of an embodiment of suchwireless communication devices are described in greater detail withreference to FIG. 2B among other diagrams.

Some examples of possible devices that may be implemented to operate inaccordance with any of the various examples, embodiments, options,and/or their equivalents, etc. described herein may include, but are notlimited by, appliances within homes, businesses, etc. such asrefrigerators, microwaves, heaters, heating systems, air conditioners,air conditioning systems, lighting control systems, and/or any othertypes of appliances, etc.; meters such as for natural gas service,electrical service, water service, Internet service, cable and/orsatellite television service, and/or any other types of meteringpurposes, etc.; devices wearable on a user or person including watches,monitors such as those that monitor activity level, bodily functionssuch as heartbeat, breathing, bodily activity, bodily motion or lackthereof, etc.; medical devices including intravenous (IV) medicinedelivery monitoring and/or controlling devices, blood monitoring devices(e.g., glucose monitoring devices) and/or any other types of medicaldevices, etc.; premises monitoring devices such as movementdetection/monitoring devices, door closed/ajar detection/monitoringdevices, security/alarm system monitoring devices, and/or any other typeof premises monitoring devices; multimedia devices includingtelevisions, computers, audio playback devices, video playback devices,and/or any other type of multimedia devices, etc.; and/or generally anyother type(s) of device(s) that include(s) wireless communicationcapability, functionality, circuitry, etc. In general, any device thatis implemented to support wireless communications may be implemented tooperate in accordance with any of the various examples, embodiments,options, and/or their equivalents, etc. described herein.

The base stations (BSs) or access points (APs) 112-116 are operablycoupled to the network hardware 134 via local area network connections136, 138, and 140. The network hardware 134, which may be a router,switch, bridge, modem, system controller, etc., provides a wide areanetwork connection 142 for the communication system 100. Each of thebase stations or access points 112-116 has an associated antenna orantenna array to communicate with the wireless communication devices inits area. Typically, the wireless communication devices register with aparticular base station or access point 112-116 to receive services fromthe communication system 100. For direct connections (i.e.,point-to-point communications), wireless communication devicescommunicate directly via an allocated channel.

Any of the various wireless communication devices (WDEVs) 118-132 andBSs or APs 112-116 may include a processor and/or a communicationinterface to support communications with any other of the wirelesscommunication devices 118-132 and BSs or APs 112-116. In an example ofoperation, a processor and/or a communication interface implementedwithin one of the devices (e.g., any one of the WDEVs 118-132 and BSs orAPs 112-116) is/are configured to process at least one signal receivedfrom and/or to generate at least one signal to be transmitted to anotherone of the devices (e.g., any other one of the WDEVs 118-132 and BSs orAPs 112-116). Note that general reference to a communication device,such as a wireless communication device (e.g., WDEVs) 118-132 and BSs orAPs 112-116 in FIG. 1, or any other communication devices and/orwireless communication devices may alternatively be made generallyherein using the term ‘device’ (e.g., with respect to FIG. 2A below,“device 210” when referring to “wireless communication device 210” or“WDEV 210,” or “devices 210-234” when referring to “wirelesscommunication devices 210-234”; or with respect to FIG. 2B below, use of“device 310” may alternatively be used when referring to “wirelesscommunication device 310”, or “devices 390 and 391 (or 390-391)” whenreferring to wireless communication devices 390 and 391 or WDEVs 390 and391). Generally, such general references or designations of devices maybe used interchangeably.

The processor and/or the communication interface of any one of thevarious devices, WDEVs 118-132 and BSs or APs 112-116, may be configuredto support communications with any other of the various devices, WDEVs118-132 and BSs or APs 112-116. Such communications may beuni-directional or bi-directional between devices. Also, suchcommunications may be uni-directional between devices at one time andbi-directional between those devices at another time.

In an example, a device (e.g., any one of the WDEVs 118-132 and BSs orAPs 112-116) includes a communication interface and/or a processor (andpossibly other possible circuitries, components, elements, etc.) tosupport communications with other device(s) and to generate and processsignals for such communications. The communication interface and/or theprocessor operate to perform various operations and functions toeffectuate such communications (e.g., the communication interface andthe processor may be configured to perform certain operation(s) inconjunction with one another, cooperatively, dependently with oneanother, etc. and other operation(s) separately, independently from oneanother, etc.). In some examples, such a processor includes allcapability, functionality, and/or circuitry, etc. to perform suchoperations as described herein. In some other examples, such acommunication interface includes all capability, functionality, and/orcircuitry, etc. to perform such operations as described herein. In evenother examples, such a processor and a communication interface includeall capability, functionality, and/or circuitry, etc. to perform suchoperations as described herein, at least in part, cooperatively with oneanother.

In an example of implementation and operation, a wireless communicationdevice (e.g., any one of the WDEVs 118-132 and BSs or APs 112-116)includes a processor that generates a first orthogonal frequencydivision multiple access (OFDMA) packet for transmission via a firstcommunication channel. In some examples, the first OFDMA packet includesa first short training field (STF) that includes a base binary sequencemapped onto a plurality of OFDMA sub-carriers based on a predeterminedspacing pattern, wherein the base binary sequence includes values of +1and −1. The processor generates a second OFDMA packet for transmissionvia a second communication channel. In some examples, the second OFDMApacket includes a second STF that includes the base binary sequencefollowed by 0 followed by a phased rotated version of the base binarysequence. Then, the processor transmits the first OFDMA packet to afirst other wireless communication device via the first communicationchannel and transmit the second OFDMA packet to at least one of thefirst other wireless communication device or a second wirelesscommunication device via the second communication channel.

FIG. 2A is a diagram illustrating an embodiment 200 of dense deploymentof wireless communication devices (shown as WDEVs in the diagram). Anyof the various WDEVs 210-234 may be access points (APs) or wirelessstations (STAs). For example, WDEV 210 may be an AP or an AP-operativeSTA that communicates with WDEVs 212, 214, 216, and 218 that are STAs.WDEV 220 may be an AP or an AP-operative STA that communicates withWDEVs 222, 224, 226, and 228 that are STAs. In certain instances, atleast one additional AP or AP-operative STA may be deployed, such asWDEV 230 that communicates with WDEVs 232 and 234 that are STAs. TheSTAs may be any type of one or more wireless communication device typesincluding wireless communication devices 118-132, and the APs orAP-operative STAs may be any type of one or more wireless communicationdevices including as BSs or APs 112-116. Different groups of the WDEVs210-234 may be partitioned into different basic services sets (BSSs). Insome instances, at least one of the WDEVs 210-234 are included within atleast one overlapping basic services set (OBSS) that cover two or moreBSSs. As described above with the association of WDEVs in an AP-STArelationship, one of the WDEVs may be operative as an AP and certain ofthe WDEVs can be implemented within the same basic services set (BSS).

This disclosure presents novel architectures, methods, approaches, etc.that allow for improved spatial re-use for next generation WiFi orwireless local area network (WLAN) systems. Next generation WiFi systemsare expected to improve performance in dense deployments where manyclients and APs are packed in a given area (e.g., which may be an area[indoor and/or outdoor] with a high density of devices, such as a trainstation, airport, stadium, building, shopping mall, arenas, conventioncenters, colleges, downtown city centers, etc. to name just someexamples). Large numbers of devices operating within a given area can beproblematic if not impossible using prior technologies.

In an example of implementation and operation, WDEV 216 generates afirst OFDMA packet for transmission via a first communication channel,wherein the first OFDMA packet includes a first STF that includes a basebinary sequence mapped onto a plurality of OFDMA sub-carriers based on apredetermined spacing pattern, wherein the base binary sequence includesvalues of +1 and −1. The processor generates generate a second OFDMApacket for transmission via a second communication channel, wherein thesecond OFDMA packet includes a second STF that includes the base binarysequence followed by 0 followed by a phased rotated version of the basebinary sequence. Then, the processor transmits the first OFDMA packet toa first other wireless communication device via the first communicationchannel and transmit the second OFDMA packet to at least one of thefirst other wireless communication device or a second wirelesscommunication device via the second communication channel.

FIG. 2B is a diagram illustrating an example 202 of communicationbetween wireless communication devices. A wireless communication device310 (e.g., which may be any one of devices 118-132 as with reference toFIG. 1) is in communication with another wireless communication device390 (and/or any number of other wireless communication devices upthrough another wireless communication device 391) via a transmissionmedium. The wireless communication device 310 includes a communicationinterface 320 to perform transmitting and receiving of at least onesignal, symbol, packet, frame, etc. (e.g., using a transmitter 322 and areceiver 324) (note that general reference to packet or frame may beused interchangeably).

Generally speaking, the communication interface 320 is implemented toperform any such operations of an analog front end (AFE) and/or physicallayer (PHY) transmitter, receiver, and/or transceiver. Examples of suchoperations may include any one or more of various operations includingconversions between the frequency and analog or continuous time domains(e.g., such as the operations performed by a digital to analog converter(DAC) and/or an analog to digital converter (ADC)), gain adjustmentincluding scaling, filtering (e.g., in either the digital or analogdomains), frequency conversion (e.g., such as frequency upscaling and/orfrequency downscaling, such as to a baseband frequency at which one ormore of the components of the device 310 operates), equalization,pre-equalization, metric generation, symbol mapping and/or de-mapping,automatic gain control (AGC) operations, and/or any other operationsthat may be performed by an AFE and/or PHY component within a wirelesscommunication device.

In some implementations, the wireless communication device 310 alsoincludes a processor 330, and an associated memory 340, to executevarious operations including interpreting at least one signal, symbol,packet, and/or frame transmitted to wireless communication device 390and/or received from the wireless communication device 390 and/orwireless communication device 391. The wireless communication devices310 and 390 (and/or 391) may be implemented using at least oneintegrated circuit in accordance with any desired configuration orcombination of components, modules, etc. within at least one integratedcircuit. Also, the wireless communication devices 310, 390, and/or 391may each include one or more antennas for transmitting and/or receivingof at least one packet or frame (e.g., WDEV 390 may include m antennae,and WDEV 391 may include n antennae).

Also, in some examples, note that one or more of the processor 330, thecommunication interface 320 (including the TX 322 and/or RX 324thereof), and/or the memory 340 may be implemented in one or more“processing modules,” “processing circuits,” “processors,” and/or“processing units”. Considering one example, one processor 330 a may beimplemented to include the processor 330, the communication interface320 (including the TX 322 and/or RX 324 thereof), and the memory 340.Considering another example, two or more processors may be implementedto include the processor 330, the communication interface 320 (includingthe TX 322 and/or RX 324 thereof), and the memory 340. In such examples,such a “processor” or “processors” is/are configured to perform variousoperations, functions, communications, etc. as described herein. Ingeneral, the various elements, components, etc. shown within the device310 may be implemented in any number of “processing modules,”“processing circuits,” “processors,” and/or “processing units” (e.g., 1,2, . . . , and generally using N such “processing modules,” “processingcircuits,” “processors,” and/or “processing units”, where N is apositive integer greater than or equal to 1).

In some examples, the device 310 includes both processor 330 andcommunication interface 320 configured to perform various operations. Inother examples, the device 310 includes processor 330 a configured toperform various operations. Generally, such operations includegenerating, transmitting, etc. signals intended for one or more otherdevices (e.g., device 390 through 391) and receiving, processing, etc.other signals received for one or more other devices (e.g., device 390through 391).

FIG. 2C is a diagram illustrating another example 203 of communicationbetween wireless communication devices. The communication interface 320of wireless communication device (WDEV) 310 is configured to receive afirst signal from another wireless communication device (e.g., WDEV 390)and/or transmit a second signal to the other wireless communicationdevice (e.g., WDEV 390). At or during a first time (time 1, or DT1), theWDEV 310 receives a packet (alternatively referred to as a frame) fromWDEV 390. Alternatively, at or during a first time (time 1, or DT1), theWDEV 310 transmits a packet (alternatively referred to as a frame) toWDEV 390. Then, at or during a second time (time 2, or DT2), the WDEV310 processes the packet determine the information therein. The framemay be implemented to include various fields including those describedbelow (e.g., short training field (STF), long training field (LTF),signal field (SIG), data, etc.). In some examples, an STF and/or LTFincluded therein is based on a sequence that is selected to reduce oreliminate peak to average power ratio (PAPR) between the STF field(and/or LTF field) and the at least one other field of the frame.

A device can process STFs and/or LTFs for many purposes including toidentify that a frame is about to start, to synchronize timers, toselect an antenna configuration, to set receiver gain, to set up certainthe modulation parameters for the remainder of the packet, to performchannel estimation for uses such as beamforming, etc. In some examples,one or more STFs are used for gain adjustment (e.g., such as automaticgain control (AGC) adjustment), and a given STF may be repeated one ormore times (e.g., repeated 1 time in one example). In some examples, oneor more LTFs are used for channel estimation, channel characterization,etc. (e.g., such as for determining a channel response, a channeltransfer function, etc.), and a given LTF may be repeated one or moretimes (e.g., repeated up to 8 times in one example).

In an example of implementation and operation, WDEV 310 generates afirst OFDMA packet for transmission via a first communication channel(e.g., a 20 MHz communication channel). In some examples, the firstOFDMA packet includes a first STF that includes a base binary sequencemapped onto a plurality of OFDMA sub-carriers based on a predeterminedspacing pattern, wherein the base binary sequence includes values of +1and −1. The WDEV 310 generates a second OFDMA packet for transmissionvia a second communication channel (e.g., a 40 MHz communicationchannel). In some examples, the second OFDMA packet includes a secondSTF that includes the base binary sequence followed by 0 followed by aphased rotated version of the base binary sequence. The WDEV 310transmits the first OFDMA packet to WDEV 390 via the first communicationchannel (e.g., a 20 MHz communication channel) and transmits the secondOFDMA packet to WDEV 390 and/or WDEV 391 via the second communicationchannel (e.g., a 40 MHz communication channel).

In another example of implementation and operation, the WDEV 310generates a third OFDMA packet that includes a third STF that includesthe base binary sequence followed by 0 followed by an inverted versionof the base binary sequence and transmits the third OFDMA packet to atleast one of the first other wireless communication device, the secondother wireless communication device, or a third wireless communicationdevice.

In another example of implementation and operation, the WDEV 310 rotatesthe first STF by 45 degrees when generating the first OFDMA packet. TheWDEV 310 also rotates the second STF by 45 degrees when generating thesecond OFDMA packet. In some examples, the predetermined spacing patternspecifies a sub-carrier spacing of 16 for elements of the base binarysequence mapped onto the plurality of OFDMA sub-carriers with indicesranging from −112 to +112.

In one example of implementation and operation, the base binary sequenceis specified as M, where M=[−1, −1 −1 +1 +1 +1 −1, +1, +1 +1 −1 +1 +1−1, +1].

In another example of implementation and operation, the WDEV 310includes both a processor to perform many of the operations describedabove and also includes a communication interface, coupled to theprocessor, that is configured to support communications within asatellite communication system, a wireless communication system, a wiredcommunication system, a fiber-optic communication system, and/or amobile communication system. The processor is configured to transmit thefirst OFDMA packet and/or the second OFDMA packet to WDEV 390 and/orWDEV 391 via the communication interface.

FIG. 3A is a diagram illustrating an example 301 of orthogonal frequencydivision multiplexing (OFDM) and/or orthogonal frequency divisionmultiple access (OFDMA). OFDM's modulation may be viewed as dividing upan available spectrum into a plurality of narrowband sub-carriers (e.g.,relatively lower data rate carriers). The sub-carriers are includedwithin an available frequency spectrum portion or band. This availablefrequency spectrum is divided into the sub-carriers or tones used forthe OFDM or OFDMA symbols and packets/frames. Note that sub-carrier ortone may be used interchangeably. Typically, the frequency responses ofthese sub-carriers are non-overlapping and orthogonal. Each sub-carriermay be modulated using any of a variety of modulation coding techniques(e.g., as shown by the vertical axis of modulated data).

A communication device may be configured to perform encoding of one ormore bits to generate one or more coded bits used to generate themodulation data (or generally, data). For example, a processor and thecommunication interface of a communication device may be configured toperform forward error correction (FEC) and/or error checking andcorrection (ECC) code of one or more bits to generate one or more codedbits. Examples of FEC and/or ECC may include turbo code, convolutionalcode, turbo trellis coded modulation (TTCM), low density parity check(LDPC) code, Reed-Solomon (RS) code, BCH (Bose and Ray-Chaudhuri, andHocquenghem) code, binary convolutional code (BCC), Cyclic RedundancyCheck (CRC), and/or any other type of ECC and/or FEC code and/orcombination thereof, etc. Note that more than one type of ECC and/or FECcode may be used in any of various implementations includingconcatenation (e.g., first ECC and/or FEC code followed by second ECCand/or FEC code, etc. such as based on an inner code/outer codearchitecture, etc.), parallel architecture (e.g., such that first ECCand/or FEC code operates on first bits while second ECC and/or FEC codeoperates on second bits, etc.), and/or any combination thereof. The oneor more coded bits may then undergo modulation or symbol mapping togenerate modulation symbols. The modulation symbols may include dataintended for one or more recipient devices. Note that such modulationsymbols may be generated using any of various types of modulation codingtechniques. Examples of such modulation coding techniques may includebinary phase shift keying (BPSK), quadrature phase shift keying (QPSK),8-phase shift keying (PSK), 16 quadrature amplitude modulation (QAM), 32amplitude and phase shift keying (APSK), etc., uncoded modulation,and/or any other desired types of modulation including higher orderedmodulations that may include even greater number of constellation points(e.g., 1024 QAM, etc.).

FIG. 3B is a diagram illustrating another example 302 of OFDM and/orOFDMA. A transmitting device transmits modulation symbols via thesub-carriers. Note that such modulation symbols may include datamodulation symbols, pilot modulation symbols (e.g., for use in channelestimation, characterization, etc.) and/or other types of modulationsymbols (e.g., with other types of information included therein). OFDMand/or OFDMA modulation may operate by performing simultaneoustransmission of a large number of narrowband carriers (or multi-tones).In some applications, a guard interval (GI) or guard space is sometimesemployed between the various OFDM symbols to try to minimize the effectsof ISI (Inter-Symbol Interference) that may be caused by the effects ofmulti-path within the communication system, which can be particularly ofconcern in wireless communication systems. In addition, a cyclic prefix(CP) and/or cyclic suffix (CS) (shown in right hand side of FIG. 3A)that may be a copy of the CP may also be employed within the guardinterval to allow switching time (e.g., such as when jumping to a newcommunication channel or sub-channel) and to help maintain orthogonalityof the OFDM and/or OFDMA symbols. Generally speaking, an OFDM and/orOFDMA system design is based on the expected delay spread within thecommunication system (e.g., the expected delay spread of thecommunication channel).

In a single-user system in which one or more OFDM symbols or OFDMpackets/frames are transmitted between a transmitter device and areceiver device, all of the sub-carriers or tones are dedicated for usein transmitting modulated data between the transmitter and receiverdevices. In a multiple user system in which one or more OFDM symbols orOFDM packets/frames are transmitted between a transmitter device andmultiple recipient or receiver devices, the various sub-carriers ortones may be mapped to different respective receiver devices asdescribed below with respect to FIG. 3C.

FIG. 3C is a diagram illustrating another example 303 of OFDM and/orOFDMA. Comparing OFDMA to OFDM, OFDMA is a multi-user version of thepopular orthogonal frequency division multiplexing (OFDM) digitalmodulation scheme. Multiple access is achieved in OFDMA by assigningsubsets of sub-carriers to individual recipient devices or users. Forexample, first sub-carrier(s)/tone(s) may be assigned to a user 1,second sub-carrier(s)/tone(s) may be assigned to a user 2, and so on upto any desired number of users. In addition, such sub-carrier/toneassignment may be dynamic among different respective transmissions(e.g., a first assignment for a first packet/frame, a second assignmentfor second packet/frame, etc.). An OFDM packet/frame may include morethan one OFDM symbol. Similarly, an OFDMA packet/frame may include morethan one OFDMA symbol. In addition, such sub-carrier/tone assignment maybe dynamic among different respective symbols within a givenpacket/frame or superframe (e.g., a first assignment for a first OFDMAsymbol within a packet/frame, a second assignment for a second OFDMAsymbol within the packet/frame, etc.). Generally speaking, an OFDMAsymbol is a particular type of OFDM symbol, and general reference toOFDM symbol herein includes both OFDM and OFDMA symbols (and generalreference to OFDM packet/frame herein includes both OFDM and OFDMApackets/frames, and vice versa). FIG. 3C shows example 303 where theassignments of sub-carriers to different users are intermingled amongone another (e.g., sub-carriers assigned to a first user includesnon-adjacent sub-carriers and at least one sub-carrier assigned to asecond user is located in between two sub-carriers assigned to the firstuser). The different groups of sub-carriers associated with each usermay be viewed as being respective channels of a plurality of channelsthat compose all of the available sub-carriers for OFDM signaling.

FIG. 3D is a diagram illustrating another example 304 of OFDM and/orOFDMA. In this example 304, the assignments of sub-carriers to differentusers are located in different groups of adjacent sub-carriers (e.g.,first sub-carriers assigned to a first user include first adjacentlylocated sub-carrier group, second sub-carriers assigned to a second userinclude second adjacently located sub-carrier group, etc.). Thedifferent groups of adjacently located sub-carriers associated with eachuser may be viewed as being respective channels of a plurality ofchannels that compose all of the available sub-carriers for OFDMsignaling.

FIG. 3E is a diagram illustrating an example 305 of single-carrier (SC)signaling. SC signaling, when compared to OFDM signaling, includes asingular relatively wide channel across which signals are transmitted.In contrast, in OFDM, multiple narrowband sub-carriers or narrowbandsub-channels span the available frequency range, bandwidth, or spectrumacross which signals are transmitted within the narrowband sub-carriersor narrowband sub-channels.

Generally, a communication device may be configured to include aprocessor and the communication interface (or alternatively a processor,such a processor 330 a shown in FIG. 2B) configured to process receivedOFDM and/or OFDMA symbols and/or frames (and/or SC symbols and/orframes) and to generate such OFDM and/or OFDMA symbols and/or frames(and/or SC symbols and/or frames).

In prior IEEE 802.11 legacy prior standards, protocols, and/orrecommended practices, including those that operate in the 2.4 GHz and 4GHz frequency bands, certain preambles are used. For use in thedevelopment of a new standard, protocol, and/or recommended practice, anew preamble design is presented herein that permits classification ofall current preamble formats while still enabling the classification ofa new format by new devices. In addition, various embodiments, examples,designs, etc. of new short training fields (STFs) and long trainingfields (LTFs) are presented herein.

FIG. 4A is a diagram illustrating an example 401 of an OFDM/A packet.This packet includes at least one preamble symbol followed by at leastone data symbol. The at least one preamble symbol includes informationfor use in identifying, classifying, and/or categorizing the packet forappropriate processing.

FIG. 4B is a diagram illustrating another example 402 of an OFDM/Apacket of a second type. This packet also includes a preamble and data.The preamble is composed of at least one short training field (STF), atleast one long training field (LTF), and at least one signal field(SIG). The data is composed of at least one data field. In both thisexample 402 and the prior example 401, the at least one data symboland/or the at least one data field may generally be referred to as thepayload of the packet. Among other purposes, STFs and LTFs can be usedto assist a device to identify that a frame is about to start, tosynchronize timers, to select an antenna configuration, to set receivergain, to set up certain the modulation parameters for the remainder ofthe packet, to perform channel estimation for uses such as beamforming,etc. In some examples, one or more STFs are used for gain adjustment(e.g., such as automatic gain control (AGC) adjustment), and a given STFmay be repeated one or more times (e.g., repeated 1 time in oneexample). In some examples, one or more LTFs are used for channelestimation, channel characterization, etc. (e.g., such as fordetermining a channel response, a channel transfer function, etc.), anda given LTF may be repeated one or more times (e.g., repeated up to 8times in one example).

Among other purposes, the SIGs can include various information todescribe the OFDM packet including certain attributes as data rate,packet length, number of symbols within the packet, channel width,modulation encoding, modulation coding set (MCS), modulation type,whether the packet as a single or multiuser frame, frame length, etc.among other possible information. This disclosure presents a means bywhich a variable length second at least one SIG can be used to includeany desired amount of information. By using at least one SIG that is avariable length, different amounts of information may be specifiedtherein to adapt for any situation.

Various examples are described below for possible designs of a preamblefor use in wireless communications as described herein.

FIG. 4C is a diagram illustrating another example 403 of at least oneportion of an OFDM/A packet of another type. A field within the packetmay be copied one or more times therein (e.g., where N is the number oftimes that the field is copied, and N is any positive integer greaterthan or equal to one). This copy may be a cyclically shifted copy. Thecopy may be modified in other ways from the original from which the copyis made.

FIG. 4D is a diagram illustrating another example 404 of an OFDM/Apacket of a third type. In this example 404, the OFDM/A packet includesone or more fields followed by one of more first signal fields(SIG(s) 1) followed by one of more second signal fields (SIG(s) 2)followed by and one or more data field.

FIG. 4E is a diagram illustrating another example 405 of an OFDM/Apacket of a fourth type. In this example 405, the OFDM/A packet includesone or more first fields followed by one of more first signal fields(SIG(s) 1) followed by one or more second fields followed by one of moresecond signal fields (SIG(s) 2) followed by and one or more data field.

FIG. 4F is a diagram illustrating another example 406 of an OFDM/Apacket. Such a general preamble format may be backward compatible withprior IEEE 802.11 prior standards, protocols, and/or recommendedpractices.

In this example 406, the OFDM/A packet includes a legacy portion (e.g.,at least one legacy short training field (STF) shown as L-STF, legacysignal field (SIG) shown as L-SIG) and a first signal field (SIG) (e.g.,VHT [Very High Throughput] SIG (shown as SIG-A)). Then, the OFDM/Apacket includes one or more other VHT portions (e.g., VHT short trainingfield (STF) shown as VHT-STF, one or more VHT long training fields(LTFs) shown as VHT-LTF, a second SIG (e.g., VHT SIG (shown as SIG-B)),and one or more data symbols.

Various diagrams below are shown that depict at least a portion (e.g.,preamble) of various OFDM/A packet designs.

FIG. 5A is a diagram illustrating another example 501 of an OFDM/Apacket. In this example 501, the OFDM/A packet includes a signal field(SIG) and/or a repeat of that SIG that corresponds to a prior or legacycommunication standard, protocol, and/or recommended practice relativeto a newer, developing, etc. communication standard, protocol, and/orrecommended practice (shown as L-SIG/R-L-SIG) followed by a first atleast one SIG based on a newer, developing, etc. communication standard,protocol, and/or recommended practice (shown as HE-SIG-A1, e.g., whereHE corresponds to high efficiency) followed by a second at least one SIGbased on a newer, developing, etc. communication standard, protocol,and/or recommended practice (shown as HE-SIG-A2, e.g., where HE againcorresponds to high efficiency) followed by a short training field (STF)based on a newer, developing, etc. communication standard, protocol,and/or recommended practice (shown as HE-STF, e.g., where HE againcorresponds to high efficiency) followed by one or more fields.

FIG. 5B is a diagram illustrating another example 502 of an OFDM/Apacket. In this example 502, the OFDM/A packet includes a signal field(SIG) and/or a repeat of that SIG that corresponds to a prior or legacycommunication standard, protocol, and/or recommended practice relativeto a newer, developing, etc. communication standard, protocol, and/orrecommended practice (shown as L-SIG/R-L-SIG) followed by a first atleast one SIG based on a newer, developing, etc. communication standard,protocol, and/or recommended practice (shown as HE-SIG-A1, e.g., whereHE corresponds to high efficiency) followed by a second at least one SIGbased on a newer, developing, etc. communication standard, protocol,and/or recommended practice (shown as HE-SIG-A2, e.g., where HE againcorresponds to high efficiency) followed by a third at least one SIGbased on a newer, developing, etc. communication standard, protocol,and/or recommended practice (shown as HE-SIG-A3, e.g., where HE againcorresponds to high efficiency) followed by a fourth at least one SIGbased on a newer, developing, etc. communication standard, protocol,and/or recommended practice (shown as HE-SIG-A4, e.g., where HE againcorresponds to high efficiency) followed by a STF based on a newer,developing, etc. communication standard, protocol, and/or recommendedpractice (shown as HE-STF, e.g., where HE again corresponds to highefficiency) followed by one or more fields.

FIG. 5C is a diagram illustrating another example 502 of an OFDM/Apacket. In this example 503, the OFDM/A packet includes a signal field(SIG) and/or a repeat of that SIG that corresponds to a prior or legacycommunication standard, protocol, and/or recommended practice relativeto a newer, developing, etc. communication standard, protocol, and/orrecommended practice (shown as L-SIG/R-L-SIG) followed by a first atleast one SIG based on a newer, developing, etc. communication standard,protocol, and/or recommended practice (shown as HE-SIG-A1, e.g., whereHE corresponds to high efficiency) followed by a second at least one SIGbased on a newer, developing, etc. communication standard, protocol,and/or recommended practice (shown as HE-SIG-A2, e.g., where HE againcorresponds to high efficiency) followed by a third at least one SIGbased on a newer, developing, etc. communication standard, protocol,and/or recommended practice (shown as HE-SIG-B, e.g., where HE againcorresponds to high efficiency) followed by a STF based on a newer,developing, etc. communication standard, protocol, and/or recommendedpractice (shown as HE-STF, e.g., where HE again corresponds to highefficiency) followed by one or more fields. This example 503 shows adistributed SIG design that includes a first at least one SIG-A (e.g.,HE-SIG-A1 and HE-SIG-A2) and a second at least one SIG-B (e.g.,HE-SIG-B).

FIG. 5D is a diagram illustrating another example 504 of an OFDM/Apacket. This example 504 depicts a type of OFDM/A packet that includes apreamble and data. The preamble is composed of at least one shorttraining field (STF), at least one long training field (LTF), and atleast one signal field (SIG).

In this example 504, the preamble is composed of at least one shorttraining field (STF) that corresponds to a prior or legacy communicationstandard, protocol, and/or recommended practice relative to a newer,developing, etc. communication standard, protocol, and/or recommendedpractice (shown as L-STF(s)) followed by at least one long trainingfield (LTF) that corresponds to a prior or legacy communicationstandard, protocol, and/or recommended practice relative to a newer,developing, etc. communication standard, protocol, and/or recommendedpractice (shown as L-LTF(s)) followed by at least one SIG thatcorresponds to a prior or legacy communication standard, protocol,and/or recommended practice relative to a newer, developing, etc.communication standard, protocol, and/or recommended practice (shown asL-SIG(s)) and optionally followed by a repeat (e.g., or cyclicallyshifted repeat) of the L-SIG(s) (shown as RL-SIG(s)) followed by anotherat least one SIG based on a newer, developing, etc. communicationstandard, protocol, and/or recommended practice (shown as HE-SIG-A,e.g., where HE again corresponds to high efficiency) followed by anotherat least one STF based on a newer, developing, etc. communicationstandard, protocol, and/or recommended practice (shown as HE-STF(s),e.g., where HE again corresponds to high efficiency) followed by anotherat least one LTF based on a newer, developing, etc. communicationstandard, protocol, and/or recommended practice (shown as HE-LTF(s),e.g., where HE again corresponds to high efficiency) followed by atleast one packet extension followed by one or more fields.

FIG. 5E is a diagram illustrating another example 505 of an OFDM/Apacket. In this example 505, the preamble is composed of at least onefield followed by at least one SIG that corresponds to a prior or legacycommunication standard, protocol, and/or recommended practice relativeto a newer, developing, etc. communication standard, protocol, and/orrecommended practice (shown as L-SIG(s)) and optionally followed by arepeat (e.g., or cyclically shifted repeat) of the L-SIG(s) (shown asRL-SIG(s)) followed by another at least one SIG based on a newer,developing, etc. communication standard, protocol, and/or recommendedpractice (shown as HE-SIG-A, e.g., where HE again corresponds to highefficiency) followed by one or more fields.

Note that information included in the various fields in the variousexamples provided herein may be encoded using various encoders. In someexamples, two independent binary convolutional code (BCC) encoders areimplemented to encode information corresponding to different respectivemodulation coding sets (MCSs) that are can be selected and/or optimizedwith respect to, among other things, the respective payload on therespective channel. Various communication channel examples are describedwith respect to FIG. 7D below.

Also, in some examples, a wireless communication device generatescontent that is included in the various SIGs (e.g., SIGA and/or SIGB) tosignal MCS(s) to one or more other wireless communication devices toinstruct which MCS(s) for those one or more other wireless communicationdevices to use with respect to one or more communications. In addition,in some examples, content included in a first at least one SIG (e.g.,SIGA) include information to specify at least one operational parameterfor use in processing a second at least one SIG (e.g., SIGB) within thesame OFDM/A packet.

Various OFDM/A frame structures are presented herein for use incommunications between wireless communication devices and specificallyshowing OFDM/A frame structures corresponding to one or more resourceunits (RUs). Such OFDM/A frame structures may include one or more RUs.Note that these various examples may include different total numbers ofsub-carriers, different numbers of data sub-carriers, different numbersof pilot sub-carriers, etc. Different RUs may also have different othercharacteristics (e.g., different spacing between the sub-carriers,different sub-carrier densities, implemented within different frequencybands, etc.).

FIG. 6A is a diagram illustrating an example 601 of selection amongdifferent OFDM/A frame structures for use in communications betweenwireless communication devices and specifically showing OFDM/A framestructures corresponding to one or more resource units (RUs). Thisdiagram may be viewed as having some similarities to allocation ofsub-carriers to different users as shown in FIG. 4D and also shows howeach OFDM/A frame structure is associated with one or more RUs. Notethat these various examples may include different total numbers ofsub-carriers, different numbers of data sub-carriers, different numbersof pilot sub-carriers, etc. Different RUs may also have different othercharacteristics (e.g., different spacing between the sub-carriers,different sub-carrier densities, implemented within different frequencybands, etc.).

In one example, OFDM/A frame structure 1 351 is composed of at least oneRU 1 651. In one example, OFDM/A frame structure 1 351 is composed of atleast one RU 1 651 and at least one RU 2 652. In another example, OFDM/Aframe structure 1 351 is composed of at least one RU 1 651, at least oneRU 2 652, and at least one RU m 653. Similarly, the OFDM/A framestructure 2 352 up through OFDM/A frame structure n 353 may be composedof any combinations of the various RUs (e.g., including any one or moreRU selected from the RU 1 651 through RU m 653).

FIG. 6B is a diagram illustrating an example 602 of various types ofdifferent resource units (RUs). In this example 602, RU 1 651 includesA1 total sub-carrier(s), A2 data (D) sub-carrier(s), A3 pilot (P)sub-carrier(s), and A4 unused sub-carrier(s). RU 2 652 includes B1 totalsub-carrier(s), B2 D sub-carrier(s), B3 P sub-carrier(s), and B4 unusedsub-carrier(s). RU N 653 includes C1 total sub-carrier(s), C2 Dsub-carrier(s), C3 P sub-carrier(s), and C4 unused sub-carrier(s).

Considering the various RUs (e.g., across RU 1 651 to RU N 653), thetotal number of sub-carriers across the RUs increases from RU 1 651 toRU N 653 (e.g., A1<B1<C1). Also, considering the various RUs (e.g.,across RU 1 651 to RU N 653), the ratio of pilot sub-carriers to datasub-carriers across the RUs decreases from RU 1 651 to RU N 653 (e.g.,A3/A2>B3/B2>C3/C2).

In some examples, note that different RUs can include a different numberof total sub-carriers and a different number of data sub-carriers yetinclude a same number of pilot sub-carriers.

As can be seen, this disclosure presents various options for mapping ofdata and pilot sub-carriers (and sometimes unused sub-carriers thatinclude no modulation data or are devoid of modulation data) into OFDMAframes or packets (note that frame and packet may be usedinterchangeably herein) in various communications between communicationdevices including both the uplink (UL) and downlink (DL) such as withrespect to an access point (AP). Note that a user may generally beunderstood to be a wireless communication device implemented in awireless communication system (e.g., a wireless station (STA) or anaccess point (AP) within a wireless local area network (WLAN/WiFi)). Forexample, a user may be viewed as a given wireless communication device(e.g., a wireless station (STA) or an access point (AP), or anAP-operative STA within a wireless communication system). Thisdisclosure discussed localized mapping and distributed mapping of suchsub-carriers or tones with respect to different users in an OFDMAcontext (e.g., such as with respect to FIG. 4C and FIG. 4D includingallocation of sub-carriers to one or more users).

Some versions of the IEEE 802.11 standard have the following physicallayer (PHY) fast Fourier transform (FFT) sizes: 32, 64, 128, 256, 512.

These PHY FFT sizes are mapped to different bandwidths (BWs) (e.g.,which may be achieved using different downclocking ratios or factorsapplied to a first clock signal to generate different other clocksignals such as a second clock signal, a third clock signal, etc.). Inmany locations, this disclosure refers to FFT sizes instead of BW sinceFFT size determines a user's specific allocation of sub-carriers, RUs,etc. and the entire system BW using one or more mappings ofsub-carriers, RUs, etc.

This disclosure presents various ways by which the mapping of N user'sdata into the system BW tones (localized or distributed). For example,if the system BW uses 256 FFT, modulation data for 8 different users caneach use a 32 FFT, respectively. Alternatively, if the system BW uses256 FFT, modulation data for 4 different users can each use a 64 FFT,respectively. In another alternative, if the system BW uses 256 FFT,modulation data for 2 different users can each use a 128 FFT,respectively. Also, any number of other combinations is possible withunequal BW allocated to different users such as 32 FFT to 2 users, 64FFT for one user, and 128 FFT for the last user.

Localized mapping (e.g., contiguous sub-carrier allocations to differentusers such as with reference to FIG. 3D) is preferable for certainapplications such as low mobility users (e.g., that remain stationary orsubstantially stationary and whose location does not change frequently)since each user can be allocated to a sub-band based on at least onecharacteristic. An example of such a characteristic includes allocationto a sub-band that maximizes its performance (e.g., highest SNR orhighest capacity in multi-antenna system). The respective wirelesscommunication devices (users) receive frames or packets (e.g., beacons,null data packet (NDP), data, etc. and/or other frame or packet types)over the entire band and feedback their preferred sub-band or a list ofpreferred sub-bands. Alternatively, a first device (e.g., transmitter,AP, or STA) transmits at least one OFDMA packet to a secondcommunication device, and the second device (e.g., receiver, a STA, oranother STA) may be configured to measure the first device's initialtransmission occupying the entire band and choose a best/good orpreferable sub-band. The second device can be configured to transmit theselection of the information to the first device via feedback, etc.

In some examples, a device is configured to employ PHY designs for 32FFT, 64 FFT and 128 FFT as OFDMA blocks inside of a 256 FFT system BW.When this is done, there can be some unused sub-carriers (e.g., holes ofunused sub-carriers within the provisioned system BW being used). Thiscan also be the case for the lower FFT sizes. In some examples, when anFFT is an integer multiple of another, the larger FFT can be a duplicatea certain number of times of the smaller FFT (e.g., a 512 FFT can be anexact duplicate of two implementations of 256 FFT). In some examples,when using 256 FFT for system BW the available number of tones is 242that can be split among the various users that belong to the OFDMA frameor packet (DL or UL).

In some examples, a PHY design can leave gaps of sub-carriers betweenthe respective wireless communication devices (users) (e.g., unusedsub-carriers). For example, users 1 and 4 may each use a 32 FFTstructure occupying a total of 26×2=52 sub-carriers, user 2 may use a 64FFT occupying 56 sub-carriers and user 3 may use 128 FFT occupying 106sub-carriers adding up to a sum total of 214 sub-carriers leaving 28sub-carriers unused.

In another example, only 32 FFT users are multiplexed allowing up to 9users with 242 sub-carriers—(9 users×26 RUs)=8 unused sub-carriersbetween the users. In yet another example, for 64 FFT users aremultiplexed with 242 sub-carriers—(4 users×56 RUs)=18 unusedsub-carriers.

The unused sub-carriers can be used to provide better separation betweenusers especially in the UL where users's energy can spill into eachother due to imperfect time/frequency/power synchronization creatinginter-carrier interference (ICI).

FIG. 7A is a diagram illustrating another example 701 of various typesof different RUs. In this example 701, RU 1 includes X1 totalsub-carrier(s), X2 data (D) sub-carrier(s), X3 pilot (P) sub-carrier(s),and X4 unused sub-carrier(s). RU 2 includes Y1 total sub-carrier(s), Y2D sub-carrier(s), Y3 P sub-carrier(s), and Y4 unused sub-carrier(s). RUq includes Z1 total sub-carrier(s), Z2 D sub-carrier(s), Z3 Psub-carrier(s), and Z4 unused sub-carrier(s). In this example 701, notethat different RUs can include different spacing between thesub-carriers, different sub-carrier densities, implemented withindifferent frequency bands, span different ranges within at least onefrequency band, etc.

FIG. 7B is a diagram illustrating another example 702 of various typesof different RUs. This diagram shows RU 1 that includes 26 contiguoussub-carriers that include 24 data sub-carriers, and 2 pilotsub-carriers; RU 2 that includes 52 contiguous sub-carriers that include48 data sub-carriers, and 4 pilot sub-carriers; RU 3 that includes 106contiguous sub-carriers that include 102 data sub-carriers, and 4 pilotsub-carriers; RU 4 that includes 242 contiguous sub-carriers thatinclude 234 data sub-carriers, and 8 pilot sub-carriers; RU 5 thatincludes 484 contiguous sub-carriers that include 468 data sub-carriers,and 16 pilot sub-carriers; and RU 6 that includes 996 contiguoussub-carriers that include 980 data sub-carriers, and 16 pilotsub-carriers.

Note that RU 2 and RU 3 include a first/same number of pilotsub-carriers (e.g., 4 pilot sub-carriers each), and RU 5 and RU 6include a second/same number of pilot sub-carriers (e.g., 16 pilotsub-carriers each). The number of pilot sub-carriers remains same orincreases across the RUs. Note also that some of the RUs include aninteger multiple number of sub-carriers of other

RUs (e.g., RU 2 includes 52 total sub-carriers, which is 2× the 26 totalsub-carriers of RU 1, and RU 5 includes 242 total sub-carriers, which is2× the 242 total sub-carriers of RU 4).

FIG. 7C is a diagram illustrating an example 703 of various types ofcommunication protocol specified physical layer (PHY) fast Fouriertransform (FFT) sizes. The device 310 is configured to generate andtransmit OFDMA packets based on various PHY FFT sizes as specifiedwithin at least one communication protocol. Some examples of PHY FFTsizes, such as based on IEEE 802.11, include PHY FFT sizes such as 32,64, 128, 256, 512, 1024, and/or other sizes.

In one example, the device 310 is configured to generate and transmit anOFDMA packet based on RU 1 that includes 26 contiguous sub-carriers thatinclude 24 data sub-carriers, and 2 pilot sub-carriers and to transmitthat OFDMA packet based on a PHY FFT 32 (e.g., the RU 1 fits within thePHY FFT 32). In one example, the device 310 is configured to generateand transmit an OFDMA packet based on RU 2 that includes 52 contiguoussub-carriers that include 48 data sub-carriers, and 4 pilot sub-carriersand to transmit that OFDMA packet based on a PHY FFT 56 (e.g., the RU 2fits within the PHY FFT 56). The device 310 uses other sized RUs forother sized PHY FFTs based on at least one communication protocol.

Note also that any combination of RUs may be used. In another example,the device 310 is configured to generate and transmit an OFDMA packetbased on two RUs based on RU 1 and one RU based on RU 2 based on a PHYFFT 128 (e.g., two RUs based on RU 1 and one RU based on RU 2 includes atotal of 104 sub-carriers). The device 310 is configured to generate andtransmit any OFDMA packets based on any combination of RUs that can fitwithin an appropriately selected PHY FFT size of at least onecommunication protocol.

Note also that any given RU may be sub-divided or partitioned intosubsets of sub-carriers to carry modulation data for one or more users(e.g., such as with respect to FIG. 3C or FIG. 3D).

FIG. 7D is a diagram illustrating an example 704 of different channelbandwidths and relationship there between. In one example, a device(e.g., the device 310) is configured to generate and transmit any OFDMApacket based on any of a number of OFDMA frame structures within variouscommunication channels having various channel bandwidths. For example, a160 MHz channel may be subdivided into two 80 MHz channels. An 80 MHzchannel may be subdivided into two 40 MHz channels. A 40 MHz channel maybe subdivided into two 20 MHz channels. Note also such channels may belocated within the same frequency band, the same frequency sub-band oralternatively among different frequency bands, different frequencysub-bands, etc.

FIG. 8A is a diagram illustrating an example 801 of a base binarysequence for use to construct a short training field (STF) for use inwireless communications. This diagram shows an example of a base binarysequence is as follows:

M=[−1, −1 −1 +1 +1 +1 −1, +1, +1 +1 −1 +1 +1 −1, +1 ]

FIG. 8B is a diagram illustrating an example 802 of various STFsequences for a first periodicity (e.g., 0.8 μsec). Some other examplesof sequences are provided below. These are shown for differentcommunication channels (e.g., 20 MHz and 40 MHz) and are for a firstperiodicity (e.g., 0.8 μsec).

For 20 MHz transmission: HES_(−112,112)(−112:16:112)=M×(1+j)×sqrt(1/2);and HES_(−112,112)(0)=0.

For 40 MHz transmission: HES_(−240,240)(−240:16:240)=[M, 0,jM]×(1+j)×sqrt(1/2).

Note that these sequences are shown both as prior Gamma and after Gamma.When Gamma is applied, then j×j=−1, and the 40 MHz sequence is properlyshown as follows:

For 40 MHz transmission: HES_(−240,240)(−240:16:240)=[M, 0,−M]×(1+j)×sqrt(1/2).

As can be seen, a first STF sequence includes the base binary sequence,M, for 20 MHz for this first periodicity (e.g., 0.8 μsec). Also, asecond STF sequence includes the base binary sequence base binarysequence followed by 0 followed by a phased rotated version of the basebinary sequence (e.g., [M, 0, jM] or [M, 0, −M]).

FIG. 8C is a diagram illustrating another example 803 of a STF sequencefor a second periodicity (e.g., 1.6 μsec). This is shown for acommunication channel (e.g., 20 MHz) and is for a second periodicity(e.g., 1.6 μsec).

20 MHz transmission: HE-STF_(−120,120)(−120:8:120)=[M, 0,−M]×(1+j)×sqrt(1/2).

HE-STF Sequence for 1.6 μsec Periodicity

In one example of implementation and operation, the base binary sequenceis specified as M, where M=[−1 −1 −1 +1 +1 +1 −1 +1 +1 +1 −1 +1 +1 −1+1].

Based on M, an 80 MHz primary sequence: HES_(prim)(−504:8:504)=[M, −1,M, −1, −M, −1, M, 0, −M, 1, M, 1, −M, 1, −M]*(1+j)*sqrt(1/2); andHES_(prim)(±504)=0.

Based on M, an 80 MHz secondary sequence: HES_(sec)(−504:8:504) [−M, 1,−M, 1, M, 1, −M, 0, −M, 1, M, 1, −M, 1, −M]*(1+j)*sqrt(1/2); andHES_(prim)(±504)=0.

Based on HES_(prim) and HES_(sec), for a 160 MHz transmission,HES(−1016:8:1016)=[HES_(prim), 0, 0, 0, HES_(sec)].

HE-STF 1.6 μsec Periodicity PAPR

This provides for peak to average power ratio (PAPR) of 160 MHz is 6.34dB, and the PAPR of all RU on secondary channel are same except for thefollowing: Center RU26 is 3.01 dB (1.94 dB in primary), and RU996 is6.97 dB (5.77 dB in primary).

HE-STF Sequence for 0.8 μsec Periodicity

Again, in one example of implementation and operation, the base binarysequence is specified as M, where M=[−1 −1 −1 +1 +1 +1 −1 +1 +1 +1 −1 +1+1 −1 +1].

Based on M, for 80 MHz primary: HES_(prim)(−496:16:496)=[M, 1, −M, 0,−M, 1, −M]*(1+j)*sqrt(1/2).

Based on M, for 80 MHz secondary: HES_(sec)(−496:16:496)=[M, 1, −M, 0,M, −1, M]*(1+j)*sqrt(1/2).

Based on M, for 160 MHz: HES(−1008:16:1008)=[HES_(prim), 0, HES_(sec)]

HE-STF 0.8 μsec Periodicity PAPR

This provides for PAPR of 160 MHz is 4.98 dB, PAPR on 80 MHz primary is4.93 dB, and PAPR on 80 MHz secondary is 4.74 dB.

FIG. 9 is a diagram illustrating an embodiment of a method 900 forexecution by one or more wireless communication devices. The method 901begins by generating a first orthogonal frequency division multipleaccess (OFDMA) packet for transmission via a first communicationchannel, wherein the first OFDMA packet includes a first short trainingfield (STF) that includes a base binary sequence mapped onto a pluralityof OFDMA sub-carriers based on a predetermined spacing pattern, whereinthe base binary sequence includes values of +1 and −1 (block 910).

The method 901 continues by generating a second OFDMA packet fortransmission via a second communication channel, wherein the secondOFDMA packet includes a second STF that includes the base binarysequence followed by 0 followed by a phased rotated version of the basebinary sequence (block 920).

The method 901 then operates by transmitting, via a communicationinterface of the wireless communication device, the first OFDMA packetto a first other wireless communication device via the firstcommunication channel (block 930).

The method 901 continues by transmitting, via the communicationinterface of the wireless communication device, the second OFDMA packetto at least one of the first other wireless communication device or asecond wireless communication device via the second communicationchannel (block 940).

It is noted that the various operations and functions described withinvarious methods herein may be performed within a wireless communicationdevice (e.g., such as by the processor 330, communication interface 320,and memory 340 or processor 330 a such as described with reference toFIG. 2B) and/or other components therein. Generally, a communicationinterface and processor in a wireless communication device can performsuch operations.

Examples of some components may include one of more baseband processingmodules, one or more media access control (MAC) layer components, one ormore physical layer (PHY) components, and/or other components, etc. Forexample, such a processor can perform baseband processing operations andcan operate in conjunction with a radio, analog front end (AFE), etc.The processor can generate such signals, packets, frames, and/orequivalents etc. as described herein as well as perform variousoperations described herein and/or their respective equivalents.

In some embodiments, such a baseband processing module and/or aprocessing module (which may be implemented in the same device orseparate devices) can perform such processing to generate signals fortransmission to another wireless communication device using any numberof radios and antennae. In some embodiments, such processing isperformed cooperatively by a processor in a first device and anotherprocessor within a second device. In other embodiments, such processingis performed wholly by a processor within one device.

As may be used herein, the terms “substantially” and “approximately”provides an industry-accepted tolerance for its corresponding termand/or relativity between items. Such an industry-accepted toleranceranges from less than one percent to fifty percent and corresponds to,but is not limited to, component values, integrated circuit processvariations, temperature variations, rise and fall times, and/or thermalnoise. Such relativity between items ranges from a difference of a fewpercent to magnitude differences. As may also be used herein, theterm(s) “configured to,” “operably coupled to,” “coupled to,” and/or“coupling” includes direct coupling between items and/or indirectcoupling between items via an intervening item (e.g., an item includes,but is not limited to, a component, an element, a circuit, and/or amodule) where, for an example of indirect coupling, the intervening itemdoes not modify the information of a signal but may adjust its currentlevel, voltage level, and/or power level. As may further be used herein,inferred coupling (i.e., where one element is coupled to another elementby inference) includes direct and indirect coupling between two items inthe same manner as “coupled to”. As may even further be used herein, theterm “configured to,” “operable to,” “coupled to,” or “operably coupledto” indicates that an item includes one or more of power connections,input(s), output(s), etc., to perform, when activated, one or more itscorresponding functions and may further include inferred coupling to oneor more other items. As may still further be used herein, the term“associated with,” includes direct and/or indirect coupling of separateitems and/or one item being embedded within another item.

As may be used herein, the term “compares favorably” or equivalent,indicates that a comparison between two or more items, signals, etc.,provides a desired relationship. For example, when the desiredrelationship is that signal 1 has a greater magnitude than signal 2, afavorable comparison may be achieved when the magnitude of signal 1 isgreater than that of signal 2 or when the magnitude of signal 2 is lessthan that of signal 1.

As may also be used herein, the terms “processing module,” “processingcircuit,” “processor,” and/or “processing unit” may be a singleprocessing device or a plurality of processing devices. Such aprocessing device may be a microprocessor, micro-controller, digitalsignal processor, microcomputer, central processing unit, fieldprogrammable gate array, programmable logic device, state machine, logiccircuitry, analog circuitry, digital circuitry, and/or any device thatmanipulates signals (analog and/or digital) based on hard coding of thecircuitry and/or operational instructions. The processing module,module, processing circuit, and/or processing unit may be, or furtherinclude, memory and/or an integrated memory element, which may be asingle memory device, a plurality of memory devices, and/or embeddedcircuitry of another processing module, module, processing circuit,and/or processing unit. Such a memory device may be a read-only memory,random access memory, volatile memory, non-volatile memory, staticmemory, dynamic memory, flash memory, cache memory, and/or any devicethat stores digital information. Note that if the processing module,module, processing circuit, and/or processing unit includes more thanone processing device, the processing devices may be centrally located(e.g., directly coupled together via a wired and/or wireless busstructure) or may be distributedly located (e.g., cloud computing viaindirect coupling via a local area network and/or a wide area network).Further note that if the processing module, module, processing circuit,and/or processing unit implements one or more of its functions via astate machine, analog circuitry, digital circuitry, and/or logiccircuitry, the memory and/or memory element storing the correspondingoperational instructions may be embedded within, or external to, thecircuitry comprising the state machine, analog circuitry, digitalcircuitry, and/or logic circuitry. Still further note that, the memoryelement may store, and the processing module, module, processingcircuit, and/or processing unit executes, hard coded and/or operationalinstructions corresponding to at least some of the steps and/orfunctions illustrated in one or more of the Figures. Such a memorydevice or memory element can be included in an article of manufacture.

One or more embodiments of an invention have been described above withthe aid of method steps illustrating the performance of specifiedfunctions and relationships thereof. The boundaries and sequence ofthese functional building blocks and method steps have been arbitrarilydefined herein for convenience of description. Alternate boundaries andsequences can be defined so long as the specified functions andrelationships are appropriately performed. Any such alternate boundariesor sequences are thus within the scope and spirit of the claims.Further, the boundaries of these functional building blocks have beenarbitrarily defined for convenience of description. Alternate boundariescould be defined as long as the certain significant functions areappropriately performed. Similarly, flow diagram blocks may also havebeen arbitrarily defined herein to illustrate certain significantfunctionality. To the extent used, the flow diagram block boundaries andsequence could have been defined otherwise and still perform the certainsignificant functionality. Such alternate definitions of both functionalbuilding blocks and flow diagram blocks and sequences are thus withinthe scope and spirit of the claimed invention. One of average skill inthe art will also recognize that the functional building blocks, andother illustrative blocks, modules and components herein, can beimplemented as illustrated or by discrete components, applicationspecific integrated circuits, processors executing appropriate softwareand the like or any combination thereof.

The one or more embodiments are used herein to illustrate one or moreaspects, one or more features, one or more concepts, and/or one or moreexamples of the invention. A physical embodiment of an apparatus, anarticle of manufacture, a machine, and/or of a process may include oneor more of the aspects, features, concepts, examples, etc. describedwith reference to one or more of the embodiments discussed herein.Further, from figure to figure, the embodiments may incorporate the sameor similarly named functions, steps, modules, etc. that may use the sameor different reference numbers and, as such, the functions, steps,modules, etc. may be the same or similar functions, steps, modules, etc.or different ones.

Unless specifically stated to the contra, signals to, from, and/orbetween elements in a figure of any of the figures presented herein maybe analog or digital, continuous time or discrete time, and single-endedor differential. For instance, if a signal path is shown as asingle-ended path, it also represents a differential signal path.Similarly, if a signal path is shown as a differential path, it alsorepresents a single-ended signal path. While one or more particulararchitectures are described herein, other architectures can likewise beimplemented that use one or more data buses not expressly shown, directconnectivity between elements, and/or indirect coupling between otherelements as recognized by one of average skill in the art.

The term “module” is used in the description of one or more of theembodiments. A module includes a processing module, a processor, afunctional block, hardware, and/or memory that stores operationalinstructions for performing one or more functions as may be describedherein. Note that, if the module is implemented via hardware, thehardware may operate independently and/or in conjunction with softwareand/or firmware. As also used herein, a module may contain one or moresub-modules, each of which may be one or more modules.

While particular combinations of various functions and features of theone or more embodiments have been expressly described herein, othercombinations of these features and functions are likewise possible. Thepresent disclosure of an invention is not limited by the particularexamples disclosed herein and expressly incorporates these othercombinations.

What is claimed is:
 1. A wireless communication device comprising: aprocessor configured to: generate a first orthogonal frequency divisionmultiple access (OFDMA) packet for transmission via a firstcommunication channel, wherein the first OFDMA packet includes a firstshort training field (STF) that includes a base binary sequence mappedonto a plurality of OFDMA sub-carriers based on a predetermined spacingpattern, wherein the base binary sequence includes values of +1 and −1;generate a second OFDMA packet for transmission via a secondcommunication channel, wherein the second OFDMA packet includes a secondSTF that includes the base binary sequence followed by 0 followed by aphased rotated version of the base binary sequence; transmit the firstOFDMA packet to a first other wireless communication device via thefirst communication channel; and transmit the second OFDMA packet to atleast one of the first other wireless communication device or a secondwireless communication device via the second communication channel. 2.The wireless communication device of claim 1, wherein the processor isfurther configured to: generate a third OFDMA packet that includes athird STF that includes the base binary sequence followed by 0 followedby an inverted version of the base binary sequence; and transmit thethird OFDMA packet to at least one of the first other wirelesscommunication device, the second other wireless communication device, ora third wireless communication device.
 3. The wireless communicationdevice of claim 1, wherein: the first communication channel includes a20 MHz communication channel; and the second communication channelincludes a 40 MHz communication channel.
 4. The wireless communicationdevice of claim 1, wherein the processor is further configured to:rotate the first STF by 45 degrees when generating the first OFDMApacket; and rotate the second STF by 45 degrees when generating thesecond OFDMA packet, wherein the predetermined spacing pattern specifiesa sub-carrier spacing of 16 for elements of the base binary sequencemapped onto the plurality of OFDMA sub-carriers with indices rangingfrom −112 to +112.
 5. The wireless communication device of claim 1,wherein the base binary sequence is specified as [−1, −1 −1 +1 +1 +1 −1,+1, +1 +1 −1 +1 +1 −1, +1].
 6. The wireless communication device ofclaim 1 further comprising: a communication interface, coupled to theprocessor, that is configured to support communications within at leastone of a satellite communication system, a wireless communicationsystem, a wired communication system, a fiber-optic communicationsystem, or a mobile communication system; and the processor configuredto transmit at least one of the first OFDMA packet or the second OFDMApacket to at least one of the first other wireless communication deviceor the second wireless communication device via the communicationinterface.
 7. The wireless communication device of claim 1 furthercomprising: a wireless station (STA), wherein at least one of the firstother wireless communication device or the second wireless communicationdevice includes an access point (AP).
 8. The wireless communicationdevice of claim 1 further comprising: an access point (AP), wherein atleast one of the first other wireless communication device or the secondwireless communication device includes a wireless station (STA).
 9. Awireless communication device comprising: a processor configured to:generate a first orthogonal frequency division multiple access (OFDMA)packet for transmission via a 20 MHz communication channel, wherein thefirst OFDMA packet includes a first short training field (STF) thatincludes a base binary sequence mapped onto a plurality of OFDMAsub-carriers based on a predetermined spacing pattern, wherein the basebinary sequence is specified as [−1, −1 −1 +1 +1 +1 −1, +1, +1 +1 −1 +1+1 −1, +1]; generate a second OFDMA packet for transmission via a 40 MHzcommunication channel, wherein the second OFDMA packet includes a secondSTF that includes the base binary sequence followed by 0 followed by aninverted version of the base binary sequence; transmit the first OFDMApacket to a first other wireless communication device via the 20 MHzcommunication channel; and transmit the second OFDMA packet to at leastone of the first other wireless communication device or a secondwireless communication device via the 40 MHz communication channel. 10.The wireless communication device of claim 9, wherein the processor isfurther configured to: rotate the first STF by 45 degrees whengenerating the first OFDMA packet; and rotate the second STF by 45degrees when generating the second OFDMA packet, wherein thepredetermined spacing pattern specifies a sub-carrier spacing of 16 forelements of the base binary sequence mapped onto the plurality of OFDMAsub-carriers with indices ranging from −112 to +112.
 11. The wirelesscommunication device of claim 9 further comprising: a communicationinterface, coupled to the processor, that is configured to supportcommunications within at least one of a satellite communication system,a wireless communication system, a wired communication system, afiber-optic communication system, or a mobile communication system; andthe processor configured to transmit at least one of the first OFDMApacket or the second OFDMA packet to at least one of the first otherwireless communication device or the second wireless communicationdevice via the communication interface.
 12. The wireless communicationdevice of claim 9 further comprising: a wireless station (STA), whereinat least one of the first other wireless communication device or thesecond wireless communication device includes an access point (AP). 13.The wireless communication device of claim 9 further comprising: anaccess point (AP), wherein at least one of the first other wirelesscommunication device or the second wireless communication deviceincludes a wireless station (STA).
 14. A method for execution by awireless communication device, the method comprising: generating a firstorthogonal frequency division multiple access (OFDMA) packet fortransmission via a first communication channel, wherein the first OFDMApacket includes a first short training field (STF) that includes a basebinary sequence mapped onto a plurality of OFDMA sub-carriers based on apredetermined spacing pattern, wherein the base binary sequence includesvalues of +1 and −1; generating a second OFDMA packet for transmissionvia a second communication channel, wherein the second OFDMA packetincludes a second STF that includes the base binary sequence followed by0 followed by a phased rotated version of the base binary sequence;transmitting, via a communication interface of the wirelesscommunication device, the first OFDMA packet to a first other wirelesscommunication device via the first communication channel; andtransmitting, via the communication interface of the wirelesscommunication device, the second OFDMA packet to at least one of thefirst other wireless communication device or a second wirelesscommunication device via the second communication channel.
 15. Themethod of claim 14 further comprising: generating a third OFDMA packetthat includes a third STF that includes the base binary sequencefollowed by 0 followed by an inverted version of the base binarysequence; and transmitting, via the communication interface of thewireless communication device, the third OFDMA packet to at least one ofthe first other wireless communication device, the second other wirelesscommunication device, or a third wireless communication device.
 16. Themethod of claim 14, wherein: the first communication channel includes a20 MHz communication channel; and the second communication channelincludes a 40 MHz communication channel.
 17. The method of claim 14further comprising: rotating the first STF by 45 degrees when generatingthe first OFDMA packet; and rotating the second STF by 45 degrees whengenerating the second OFDMA packet, wherein the predetermined spacingpattern specifies a sub-carrier spacing of 16 for elements of the basebinary sequence mapped onto the plurality of OFDMA sub-carriers withindices ranging from −112 to +112.
 18. The method of claim 14, whereinthe base binary sequence is specified as [−1, −1 −1 +1 +1 +1 −1, +1, +1+1 −1 +1 +1 −1, +1].
 19. The method of claim 14, wherein the wirelesscommunication device includes a wireless station (STA), and at least oneof the first other wireless communication device or the second wirelesscommunication device includes an access point (AP).
 20. The method ofclaim 14, wherein the wireless communication device includes an accesspoint (AP), wherein at least one of the first other wirelesscommunication device or the second wireless communication deviceincludes a wireless station (STA).